Electric precipitator



H. I. FRISBIE.

ELECTRIC PRECIPITATOR.

APPLICATION FILED JAN.6,1919.

14329237. Patented Jan. 27, 1920.

2 SHEETS-SHEET 1.

WITNESSES.

(5 3 A TTORNE).

H.,|. FRISBIE.

ELECTRIC PRECIPITATOR.

APPLICATION FILED JAN.6.1919.

Patented J an. 27, 1920.

2 SHEETSSHEET 2- WITNESSES $4 Q.

Bra jaw A T TOR/V5 X HOWARD I. FRISBIE, or ANACONDIA, MONTANA.

ELECTRIC PRECIPITATOR.

Specification of Letters Patent.

Patented Jan. 2'7, 1920.-

Application filed January 6, 1919. Serial IN 0. 269,904.

To all whom it may concern:

Be it known that I, HOWARD I. FRISBIE, a citizen of the United States, residing at Anaconda, in the county of Deerlodge and State of Montana, have invented certain new and useful Improvements in Electric Precipitators, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part hereof.

The present invention is directed to improvements in electrical fume precipitators, or systems for purifying gases by the passage thereof through a space charged at different points with static electricity, any mechanically suspended particles traversing the electric field being precipitated. The object of my improvement is to provide a field in which the electrodes are so disposed as to present to the flowing gases and their suspended impurities, a maximum number-of points of contact whereby a maximum number of the suspended particles for any given instant of time will participate in the polarity of the electrodes which they encounter, thereby permitting a maximum number of particles of opposite polarity to be mutually attracted and caused to coalesce,

said coalesced particles of neutral polarity) being again polarized and again attracted by other coalesced particles of opposite polarity until they have acquired a size and weight sufiicient to overcome the lifting power of the gases, when they naturally drop, the cleansed gases being allowed to continue onward to any suitable point of consumption or discharge. In the present embodiment of my invention the points of contact aforesaid are formed by a plurality of electrodes of opposite polarities following each other in succession, said electrodes being disposed in the path of flow of the gases from which the suspended impurities are to be precipitated. The electrodes collectively form zones or electrical fields of opposite polarity which are spaced sufficiently apart to prevent short-circuiting between the electrodes of the respective fields necessarily operating under an impressed high potential. The gases with their suspended particles traverse the successive zones or fields, the particles escaping a zone of one polarity entering the next zone of an opposite polarity; and since the particles entering any zone acquire the polarity of the electrodes of that zone and tend to repel one another they naturally are attracted while thus repelled by particles of opposite polarity from an adjacent zone, a succession of such operations causing a corresponding succession of coalescences among the particles until the coalesced masses attain a size and weight too great to be'longer sustained and they are accordingly precipitated. The invention, and the general dis- ..position of the component parts of the system or apparatus present advantages which will be fully apparent from the following detailed description in connection with the accompanying drawings in which Figure 1 represents a top plan of the precipitating chamber with a portion of the roof removed to expose the electrodes; Fig. 2 is a side elevation of the precipitating chamber with a portion of the side wall removed to expose the electrodes; Fig. 3 is a vertical cross-section on the line 33 of Fig. 1; Fig. 4 is a vertical cross-section on the line H of Fig. 1; Fig. 5 is a face elevation of a small section of the cluster of chains forming the insulated electrodes showing the manner of suspension thereof from the bus-bar; Fig. 6 is a vertical transverse section on the zig-zag line 6-6 of Fig. 5; Fig. 7 is an enlarged horizontal sectional detail on the line 7-7 of Fig. 6 taken through the bottom weight-supporting rod traversing the pipe of'the bottom grid; Fig. 8 is a face elevation of oneof the clusters of chain electrodes at the corner of the bottom grid; and Fig. 9 is a side elevation of the same cluster of chains or a view at right angles to Fig. 8.

, Referring to the drawings, C, represents a precipitating chamber or conduit having an inlet 1 for the gases to be treated, as for example smelter smoke and fumes, and 2 an outlet or exit flue for the cleansed gases;

Disposed along the chamber are clusters or a plurality of positive and negative electrodes the polarities of which are indicated in the drawings by the conventional plus (I-) and minus signs, the electrodes of one polarity (for example the negative) being insulated, while those of the opposite polarity are preferably, though not necessarily, grounded. The electrodes (both positive and negative) in the present embodiment of my invention are formed of suspended chains (or wires) 3 maintained taut by the (preferably cast iron) Weights 4 at the lower terminals of suitable rods or wires-5 Whose upper ends terminate in hooks 6 engaging the bottom links of the chains. The upper ends of the chains are suspended from hooks 7 carried by the top grid or frame composed of intersectin bars or pipes a,

electrodes being suspended from the roof of the chamber C by the hangers 8. The

rods 5 pass through the intersecting bars or pipes 0/, b, forming the bottom grid or guide, the grid being secured to, 01' supported by the rods at intervals, preferably at the corners where the rods are formed with enlargements n by which the grid is directly supported. The remaining rods pass loosely through holes'or openings 0 formed in the pipes composing the grid, thereby pernntting the bulk of the chains to move up and down through the holes traversed by the rods 5 according to the limits of construction.

In the present embodiment of my invention the upper grids of the negative or insulated electrodes are secured to U-shaped straps 9 passed around the longitudinal bars or pipes b, the arms of the straps being a mounted between and suspended from the transverse angle bus-bars 10,10, whose terminals are supported on top of the pillar insulators 11 set in the ide chambers or offcipitating chamber. at points adjacent the electrodes formed by the several clusters of chains are top and-bottom bafiles 13 and 11 respectively, said baflles being of sufiicient' depth. and extending across the full width of the chamber to insure the passage of the gases through the spaces between the chains 7 and thereby insure maximum contact of the gases with the electrical fields surrounding the electrodes. These baflies may be said to be disposed along the vertical planes of division between the electricalzones or fields formed by the several clusters of chains constituting the positive and negative elec trodes of the series, a baflle 13 and a baflie 14 being disposed in the same vertical plane. At the bottom of the chamber are disposed suitable drawers orpans 15 operating between transverse guides or rails 16 the flanges h of the rails being beveled or slopmg in opposite directions whereby the precipitated .dust will be readily shed into the pans. The pjans may be pulled out through pans being allowed to project slightlyibe- "yond the walls of the chamber so as to be readily seized by the operator or attendant.

b, said gr d in the case of t e negative or grounded are charged with electricity at high potential; and in the present embodiment of the invention I show the current derived from a generator G. connected to the step-up transformer. T, the latter being in electric connection with arectifier R driven in synchronism with the source of power, one end of the rectifier going to the line wire V which at intervals is connectedby the branches w to the members or bus-bars 10 of the negative electrodes, the opposite end of the rectifier and the positive electrodes being grounded. In the present embodiment of my invention the grounding of the positive electrodes is effected by electrically connecting the same to the ground on the rectifier R.

' As well understood in the art, the electrodes As indicated above, the positive and negative electrodes constituting the positive and negative fields should be separated sufiiciently to give the necessary electrical clearance so that the applied voltage shall not short-circuit through the charged gases. If

both electrodes are insulated they may be alike. If one set of the electrodes is grounded (as in the present example) and the other insulated, thegrounded electrode may or may not be similar to the insulated electrode. Where, as in the example-before us, one set of electrode is grounded (the positive here) it is not necessary inorder to prevent short circuiting, to allow for any material amount of wall or roof clearance for such grounded electrode; and it is for this reason that in the construction here shown the grids of the positive electrodes extend substantially the full width of the precipitating chamber. In such cases the clearance need be confined to the insulated electrodes only, and in the present example it will be seen that the grids and chains of the negative or insulated electrodes are spaced. sufliciently not only from the walls of the precipitating chamber but from the positive or grounded electrodes and their grids to prevent short circuiting through the charged gases between them. The bottom grids obviously prevent tangling of the chains 3 (or their equivalents), the free play of the chains through the grids resulting in a. flexible construction permitting a ready handling for purposes of repair or any other purpose. I do not wish to be restricted to the details here shown as they may be changed in many particulars coming withinthe'purview of the skilled mechanic without in any wise departing from the nature or spirit of the invention. In this connection it may be stated that any equivalent for the chain electrode may be substituted; a the sides of the chamber, the ends of the" different form of insulator for the pillar insulator here-shown may be substituted; different means of suspension may be employed. In fact a totally different design may be substituted without in any wise departing from the basic principle of the invention.

The operation may be stated in a few words: As the gases and fumes traverse the precipitating chamber the suspended particles encountering the successive zones or electrical fieldswill be caused to coalesce in the manner previously pointed out and be precipitated to the bottom of the chamber into the pans 15 from which the dust is subsequently removed.

Having described my invention what I claim is:

1. In an electric precipitator, a precipitating chamber having an inlet and an outlet and traversable by gases between said inlet and outlet, suitable electrodes disposed across the chamber and forming collectively zones or fields of opposite polarity, the electrodes forming the zones of one polarity extending substantially the width of the precipitating chamber, the electrodes forming the zones of the opposite polarity being spaced a suitable distance from the walls of the chamber, and from the first mentioned electrodes to prevent short circuiting therewith, whereby a circuitous course is insured for the gases and a maximum precipitation results.

2. In an electric precipitator, a precipitating chamber having an inlet and an outlet and traversable by gases between said inlet and outlet, said chamber having electrically conducting walls, suitable electrodes disposed across the chamber and forming collectively zones or fields of opposite polarity, the electrodes of one polarity being insulated from, and those of the opposite polarity being connected to, the chamber walls, one set of electrodes extending substantially the width of the chamber, and the other terminating a suitable distance from the side walls of the chamber, and from the first mentioned set to prevent short-circuiting therewith, and suitable bafprecipitating chamber through openings formed in the walls of the chamber, suitable insulators in said side chambers, busbars supported by said insulators and extending across the precipitating chamber through the openings aforesaid, a plurality of charged electrode elements of a given polarity suspended from the bus-bars across the path of the gases and spaced sufliciently from the walls of the precipitating chamber to form gas passages and prevent short circuiting with said walls, a plurality of charged electrode elements of opposite polarity suspended from the roof of the precipitating chamber across the path of the 1glases at points removed sufficiently from the rst mentioned electrode to prevent short circuiting between the two sets of electrodes, the second mentioned electrodes extending substantially the width of the precipitating chamber, the several electrodes forming a succession of fields of opposite polarity throughout the chamber, and suitable baffles disposed in vertical planes separating the several zones to cause the gases to pass through thezones, whereby the suspended particles are caused to coalesce and be precipitated to the bottom of the chamber.

In testimony whereof I aflix my signature, in presence of two witnesses.

HOWARD I. FRISBIE. Witnesses: v

G110. W. SPARROW, RAY A. CoBBURN.

diametrically opposite 

